@article{30df36103d7c45cebc4b29ebd4181513,
title = "The Impacts of a Subglacial Discharge Plume on Calving, Submarine Melting, and M{\'e}lange Mass Loss at Helheim Glacier, South East Greenland",
abstract = "Almost half of the Greenland ice sheet's mass loss occurs through iceberg calving at marine terminating glaciers. The presence of buoyant subglacial discharge plumes at these marine termini are thought to increase mass loss both through submarine melting and by undercutting that consequently increases calving rates. Plume models are used to predict submarine melting and undercutting. However, there are few observations that allow these relationships to be tested. Here, we use airborne lidar from the terminus of Helheim Glacier, SE Greenland to measure the bulge induced at the surface by the upwelling plume. We use these measurements to estimate plume discharge rates using a high-resolution, three-dimensional plume model. Multiyear observations of the plume are compared to a record of calving from camera and icequake data. We find no evidence to suggest that the presence of a plume, determined by its visibility at the surface, increases the frequency of major calving events and also show that mass loss at the terminus driven directly by plume discharge is significantly less than mass loss from major calving events. The results suggest that the contribution of direct plume-driven mass loss at deep marine-terminating glaciers may be less than at shallower termini.",
keywords = "Greenland, calving, glacier, lidar, melange, plume",
author = "Alistair Everett and Tavi Murray and Nick Selmes and David Holland and Reeve, {Dominic E.}",
note = "Funding Information: This work was funded by a Swansea University PhD Scholarship held by A. Everett, further support came from the Norwegian Polar Institute's Centre for Ice, Climate and Ecosystems (ICE) as part of the TIGRIF (RCN project number 243808/E40) and TW‐ICE research programmes. N. Selmes and field collection of lidar data were supported by NERC Grant NE/1007148 held by T. Murray. Lidar collection was undertaken by the NERC ARSF. Compute time on the UK National Supercomputing Service ARCHER was provided through a grant from the NERC HPC Steering Committee to A. Everett. We thank Ian Rutt, Violetta Moloney, and Martin O'Leary for valuable discussions during this work. D. Holland is thankful for support from the NSF grant ARC 13‐04137 and NYU Abu Dhabi grant G1204. We would also like to thank Neil Fraser and two anonymous reviewers whose comments helped to improve this manuscript. Funding Information: This work was funded by a Swansea University PhD Scholarship held by A. Everett, further support came from the Norwegian Polar Institute's Centre for Ice, Climate and Ecosystems (ICE) as part of the TIGRIF (RCN project number 243808/E40) and TW-ICE research programmes. N. Selmes and field collection of lidar data were supported by NERC Grant NE/1007148 held by T. Murray. Lidar collection was undertaken by the NERC ARSF. Compute time on the UK National Supercomputing Service ARCHER was provided through a grant from the NERC HPC Steering Committee to A. Everett. We thank Ian Rutt, Violetta Moloney, and Martin O'Leary for valuable discussions during this work. D. Holland is thankful for support from the NSF grant ARC 13-04137 and NYU Abu Dhabi grant G1204. We would also like to thank Neil Fraser and two anonymous reviewers whose comments helped to improve this manuscript. Publisher Copyright: {\textcopyright} 2021. American Geophysical Union. All Rights Reserved.",
year = "2021",
month = mar,
doi = "10.1029/2020JF005910",
language = "English (US)",
volume = "126",
journal = "Journal of Geophysical Research: Earth Surface",
issn = "2169-9011",
number = "3",
}